07
Alternative energy sources (solar energy)
95104881 Kakkonde geothermal plant uses hybrid cooling Kast,G. A. and Adams. S. D. MPS, Modern Power Systems, Apr. 1995, 15, (4X 39, 41. Environmental considerations play an important role in the permitting and viability of any new power plant project. These environmental considerations become even more stringent when you consider a geothermal power plant located in the middle of a National Park in Ja an. Describes the 30 MW geothermal power plant being constructed at IL& onda in Northern Japan. Modelllng flow and heat transfer In fractured rocks: 95104882 Conceptual model of a 3-D deterministic fracture network Kolditz, 0. Geothermics, Jun. 1995, 24, (3). 451-470. This work examines 3-D advective-conductive heat transfer during forced water circulation through fracturd crystalline rocks. The subject of the modelling investigation is the Hot-Dry-Rock (HDR) site at Sodtz-SousFore& Alsace, France. Fracture data from borehole logging provides an insight lo the complex structure of crystalline rocks. The proposed model is based on the general idea, that flow and advective transport in stimulated HDR reservoirs occur mainly in fractures, whose orientation is linked by the tectonic stress field. Therefore, a deterministic fracture network model is established which represents the mean geometrical features of a stimulated HDR system. 95104883 Modelllng heat extractton from forced fluid flow through stimulated fractured rock masses: Evaluation of the Soul&Sous-Forets site potentlal Bruel, D. Geohennics, Jun. 1995, 24, (3). 439-450. The paper presents the results of heat extraction modelling for a prototype Hot Dry Rock (HDR) system at the Soul&Sous-Forets site, France. The sitmificant data from the 1993 exoerimental HDR nronramme at the Soultz s& are summarized. Geological* field evidence i&ates that two major fault structures are superimposed on the four natural fracture seta used in the fracture network model. The generation of independent fracture networks allows the creation of a picture of the intersection of fractures within the borehole, which is reasonably realistic. Modelllng of a European prototype HDR reservoir 95104884 Jupc,A. J. ef aL, Geothermics, Jun. 1995, 24. (3), 403-419. The European Hot Dry Rock Geothermal Energy Project, located in the Rhine graben at So&z-sous-Fore& Alsace, France, is enterin a new phase in its development. Over the next few years the existing HDL system will be developed lo form an operational Scientific Prototype HDR System. The paper provides an introduction lo the collaborative reservoir modelling studies undertaken as part of the European Programme. In particular the paper addresses the general methodology adopted in the reservoir design process and focuses on one of the preliminary objectives of the study. assessment of the minimum HDR doublet separation required to meet the thermal performance objectives during circulation. 95104885 Modelllng tracer tests In the Rosemanowes HDR reservclr Rodriguez, N. E. et al., Geothermics, Jun. 1995, 24, (3), 375-384. Tracer tests from the Rosemanowes ICornwall. UKI Phase 2B reservoir (1985 to 1991) are fitted to a model w&h adjustable parameters. The model is a weighted sum of three similar residence time density functions. The object& was to test if components from the decomposition of surface to surface tracer tests could be correlated to different flowing zones into the production well. The results revealed that a surface to surface tracer test is msufficient to distinguish between individual flow xonez+.Bach flow zone is itself a combination of fluid with short, medium and long residence times inside the reservoir. The analysis also revealed that changes in the reservoir during circulation affected mainly the long residence time flow aths inside the reservoir, thus indicating a continuous evolution of the k asemanowes reservoir during its circulation. 95/04888
Modelln flow and heat transfer In fractured rocks: Dlmenslonal effect oB matrlx heat dlffuslon Kolditz,0. Geothe&q Jun. 1995. 24. (3). 421-437. The work examines heat transfer in fractured crystalline rocks with application to heat minin from hot dry rocks DR). The object of this study is to investigate the &m ensional effect op heat diffusion within the rock matrix. Analytical models based on the Leplacc-transform technique assume one-dunensional heat flow within the rock matrix perpendicular to the fracture plane. 95184887
The role of reservoir modelllng In fearlblllty studier for HDR geothermal rnergy exploltatlon Parker, R. H. and Jupe, A. J. Geothermics, Jun. 1995, 24, (3). 301-305.
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Fuel and Energy Abstracts September 1995
Solar
Energy
95/04888 The Australlan solar hot water heater Industry Is allve but not well Morrison, G. Solar Progress, 1995, 16, (2), 7-9. Reports that the Australian solar hot water system industry is alive but not well. Export activities provide a major source of income for many companies, but the markets tend to be volatile and subject to vagaries of import duty, currency exchange l?tp and importin& government policy. In Austraha, the energy supply utlhties have, m their competition with each other, locked out solar. A major supportive but politically unpalatible action which any government could take would be to increase energy prices to realistic levels. The author discusses the history of solar water heaters in Australia. 95/04889
Blueprlnt for better buildings t4m3+man,D. M. and Lenssen, N. Solar Today, Jul.-Aug. 1995, 9, (4), - . Tbe authors state that although the knowledge and tech11010 are available to build better buildings, builders, together with poliTm f ers, educators and lenders must learn to integrate this information mto their decisionmaking process 95104890
Bulldlngr for a rustalnable America case studier
American Solar Ener Society, 2400 Central Ave., Suite G-I, Boulder, CO.80301, USA, U2.g 32 pp. This series of articles. which first appeared in Solar Today magazine, illus-
trates passive solar energy and energy-efficient strategies. 95104891 Comment on ‘Performance predlctlon for a trlangular, built-in stora e-type solar water heater wlth transparent Insulation’ by J. $ rakash, SC. Kaushlk, R. Kumar, and H.P. Garg. (Energy-The Int. J. - 19, 889-877 (1994) Kaushika, N. D. and Arulanantham. M. Energy Aug. 1995, 20, (8), 829-831. 95104892 Comparlson of methods for ?? stlmatlng dally and hourly diffuse solar radlatlon Srivastava, S. K. et al., Applied Energy, 1995, 51. (2), 119-123. Daily and hourly diffuse radiations measured using a pyranometer and shading ring has been compared with the values calculated using several correlations. 95104893 Constructlon and rvaluatlon of a tlmber-drylng solar kiln Fu;;E I. A. and Fuwape, J. A. Bioraource Tech& 1995, 52, (3), A solar ‘timber kiln with the capacity to season 3.24 m’ of lumber was
designed, constructed and used for seasoning commercial sawnwcod. The kiln was constructed of a timber frame covered with transparent polythene sheet on the top and black leatherette on the sides. Corrugated, galvanizediron sheet painted black and tilted at 30” to the horizontal served as a heat collector. Two fans were fitted for air circulation. The kiln attained a maximum temperature of 24’ above the ambient temperature. The average efficiency of the heat collector was 38.5%. The solar kiln reduced timber drying time by 33.3-57.196 when compared with an air-drying technique. 95104894 Cooklna durlnp off-sunshlne hours usIn PCMs as storage media Domanski. R. et al., Enerav. Jul. 1995.20. (7I 607616. The possibilit of cooking &in off-s&h& kours using phase change materials (PCL s) aa storage me 8 a has been investigated experimentally. For this purpose, two concentric cylindrical vessels were constructed with 2-cm gaps. This gap was filled with stearic acid or magnesium nitrate hexahydrate as the PCMs. The cooker performance is evaluated in terms of charging and discharging times of the PCMs under different conditions. The cooker performance was found to depend strongJy on the solar intensit , massof the cooking medium, and the thermophysical properties of P E M. 95104895 A cool roof Best, J. Solar Today, Jul.-Au . 1995, 9, (4). 27-29. Describes a water-ballasted roo&ng system which provides energy savings, extended roof life and natural cooling system design alternatives. 95104898 Diffuse radlatlon models and monthly-averaae dally, diffuse data for a wide latitude range Goumathan. K. K. and Soler. A. Enernv, Jul. 1995.20, (7L 657-667. Seieral ye& of measured data on oba and &e rad;ason and sunshine duration for 40 widely spread 8’ ocations in the latitude range 36”s to 6O”N are used to develop and test models for estimating monthly-mean daily, diffuse radiation on horizontal surfaces. Applicabilit of the clearness-index (K) and sunshine fraction (S/So) models for d&e tstimaiion and the effect of combining several variables into a single multilinear equation are tested. Correlations connecting the dZfuse- to global fraction @Id/H) with K and S/So predict Hd values more accurately than their separate use.